Boiler-furnace.



PATBNTED AUG. 4, .1908.V

J. S. ROAKE. BOILER FURNACB -AP'PLxoATIoN FILED APB lli..

v the door is closed, and a sufficiently close sequent/.absence of smoke. The natural 'draft of the furnace is'suflicient to induce the ow of air` butA it willbe understood that the j invention will serve -with forced draft; under eithercondition the volumezofairmay be .controlled and regulated by the dampers E3.

order to form aclose. but separable joint between the nipple F and elbow G1 and also .to permit the doors E E on which the nipples 10 Y sleeve F1 is loosely mounted onthe project-l are' mounted lto be'openedA and lclosed, a

'end of the nipple and 'arranged to slide .teescopically thereong'guided and limited in itsmovement by pins l l'15 jl The sleeve is forced rearwardly by a in longitudinal' slots Spring F3 encircling the ni ple and abutting at one end a ainst ,a ring 4 next the sleeve and at the otIier a ainst the plate EH Thus constructed -the s eeve is yieldin ly forced 'nto Contact with the funnel-mout Gla when joint roduced.

" 'Mo ilications .may be `made in the forms and proportions of the parts Without departing from the invention. The connections from the prehe'ating chamber to thearch may. be varied and also the passages in the.

' j chamber and arch. L

-4said ehambermeans for contro of 'air through saidopenings, a discharge nipple onlsaid' doar, a hollow arch having aper-` Other forms of' eontrollngEmeans may be substituted for the dam ers arable joint mayr be di constructed.

3, and the sep- .numufh r have described 'the invention as adapte 'to heat air to be delivered through the arch, it vwill b e understood that the heat` .ed -air may befotherwise introduced to the furnace either'above 9r below the fire, and

4. tures leadingto the inteilior of the furnace, .a zstationary.pipe leading 'to the interior of said erently locatedand A `above set forth arch, and a funnel-mouth on said pipe arranged to receive said nipple and .with the latter to form a separab y jointed passage from said chamber to the interior of said arch.

2. In a furnace7 a hollow front-connection door, the interior of said door constructed to serve as an air heating chamber, said door having air inlet openings through the front plate of said door, a damper controlling said openings, a discharge nipple on the rear plate o said door, a hollow arch having apertures leading to the uma'ce, a stationary pipe leading to the interior ofsaid arch, and a yielding separable connection between said nipple and pipe.

3. In a furnace, a hollow front-connection door, the interior of which serves as an air heating chamber, a baille plate secured to the inner front wall of said door, and pins extending laterally from the rear plate of the door in opposite directions and into the passage between the baffle plate and said rear .plate, said rear` plate having a discharge o ening near its lower end, a' pipe leadingr to t e furnace, and a movable member interposed between the discharge opening and said pipe to form a close but separable joint with the latter.

4. In a furnace, a hollow front-connection door, the interior of said door constructed yto,

serve as an air heating chamber, said door havin air inlet o enings, n'rdischarge. nipple in sai dbor, 'a ho low arch/having apertures leading into theurnace, a stationary pipe leadirg to the interior of said arch, a funnelmouth on said pipe, ar sleeve on said nipple arranged to be received in said funnel-mouth,

a spring arranged to force said sleeve and into yielding contact with said funnel-mouth. In. testimony that I claim the invention I affix my signature, in presence oftwowitnesses.

JOHN s. ROAKE. Witnesses:

' CHARLES R. SEARLE,

F. E. Ecouter. 

